Very Low Shower Pressure

[keithmdw]

Looking for some guidance please.

We have a wall mount shower mixer. The bar type with an on/off tap on one side and a temperature control tap on the other.

For a long time the mixer tap has been stiff and only had a limited range of motion so we could never turn it to full cold or full hot.

Someone suggested it may be the ceramic washer degrading.

The shower worked fine for us so we left it for another time.

Just before Christmas we lost a lot of pressure on the shower but it sorted itself out.

This weekend we lost loads of pressure and it is now not much more than a dribble.

To confuse things more we have a leak on our hot water cylinder (small drip from
PRV I think).

Assume shower unrelated to leak as all other taps on house has good pressure.

Is it likely that the washer has now broken down and is blocking the flow of water? Or could this be something different. And I was told last previously that it was almost impossible to change them so likely a full tap/bar unit would be required. Does this also sound right?

Thank you

 

[just pumps]

Remove inlet pipes and check/clear filters first. Whilst there measure distance of pipe centers in case you need a new bar mixer.
Limescale can cause havoc.

 

[JohnD]

Bar type showers are for some reason cheaper and not as good as round knob mixers, even if they are the same brand.

Can you post a pic of yours, including the pipes coming out of the wall?

You have verified, by removing the shower head and letting the water gush out of the pipe or hose, that the problem is not caused by a scaly head?

 

[keithmdw]

Photo attached hopefully. It is the only one I have on my phone. Can take more when home later.

The shower head is a fixed rain shower type head. The pipe for which goes upwards on the picture.

There is also a handheld hose which comes out of the bottom on the picture.

Although we live in an area with hard water, both heads slowed to a trickle at the same time so assumed it was bar rather than an individual hose or head so haven’t checked either.

I am not that confident a DIYer so didn’t want to start dismantling the bar to check anything, if so I’ll call a plumber. Just wondering what to expect it to be.

 

[keithmdw]

Forgot to add. When using the shower you can hear a screeching/whistling noise from the bar. I assumed if something was restricting flow then the noise is the sound of water trying to force past.

Interestingly, while trying to work out which calve isolated shower last night, I turned shower on (low pressure as expected), and then turned valve off to isolate it. Found the right valve and turned it back on and shower came back with more power.

Did it a couple more times wondering if the “hit” of water as I opened the valve was moving something inside which had been blocking it.

Shower was then much better. Not normal, but much much better.

This morning while using shower it was the same as last night and much improved. My wife however flushed a toilet while I was showering which reduced pressure, though not to the dribble it had been over the weekend. Once the toilet had refilled, the pressure never came back. So not sure what is going on.

Will try blipping the water feed again tonight and see what happens.

British Gas booked for Friday to look at a leak on hot water cylinder and the low pressure (assuming not related).

One other strange thing to note. When I isolated shower, shower temperature was normal with water running. I shut off a single valve on a pipe which was cold to touch, and shower stopped completely. Surely there should have been one for hot and one for cold as the shower just mixes and doesn’t heat. And whether running well or a trickle, the temperature is never an issue.